Without limiting the scope of the invention, its background is described in connection with the transport of an agent across a membrane.
The transport of exogenous material across a biological membrane into host cells and into the cell nucleus is usually limited by the rate of the uptake of the genetic material introduced into the cells. Generally, the exogenous material diffuses through the cell; however, exogenous material may be degraded by the cell or not allowed to pass the nuclear membrane into the nucleus of the cell.